Abstract A piano is called ¡§the king of instruments¡¨. Almost every great musician writes good compositions for piano, and they are also good pianoists. Piano almost appears in every concert. Bartolomeo Cristofori made the first instrument that we recognize as a piano today in 1709.It is an important invention in music history. The basic structure of a modern piano was approximately decided in 19 century. Many patents were designed to improve the performance of piano in these years, but they didn¡¦t change the basic structure of piano. The research adopts the method of structure synthesis to design new piano and brings up a new idea ¡§linkage controls a hammer¡¨ to improve the performance of a piano.